code: def __process_transcript(file_path: str, dst_folder: str):
      """
      Converts flac files to wav from a given transcript, capturing the metadata.
      Args:
          file_path: path to a source transcript  with flac sources
          dst_folder: path where wav files will be stored
      Returns:
          a list of metadata entries for processed files.
      """
      entries = []
      root = os.path.dirname(file_path)
      with open(file_path, encoding="utf-8") as fin:
          for line in fin:
              id, text = (
                  line[: line.index(" ")],
                  line[line.index(" ") + 1 :],
              )
              transcript_text = text.lower().strip()
  
              # Convert FLAC file to WAV
              flac_file = os.path.join(root, id + ".flac")
              wav_file = os.path.join(dst_folder, id + ".wav")
              if not os.path.exists(wav_file):
                  Transformer().build(flac_file, wav_file)
              # check duration
              duration = subprocess.check_output(
                  "soxi -D {0}".format(wav_file), shell=True
              )
  
              entry = {}
              entry["audio_filepath"] = os.path.abspath(wav_file)
              entry["duration"] = float(duration)
              entry["text"] = transcript_text
              entries.append(entry)
      return entries
  
file_path: NeMo/scripts/dataset_processing/get_librispeech_data.py
imports: import argparse
  import fnmatch
  import functools
  import json
  import logging
  import multiprocessing
  import os
  import subprocess
  import tarfile
  import urllib.request
  from sox import Transformer
  from tqdm import tqdm
label_desc: Use image node_id 4 for calling a global function with example usage: __process_transcript(file_path, dst_folder) and returns: entries